Air-cooled heat exchanger tubes exposed to low ambient air temperatures (e.g., below 32° F.) will freeze rapidly if the tubes are filled with water as with a water cooler or steam condenser. There is often no way to insulate such finned air cooler tubes. In one or more embodiments herein, an apparatus is provided that solves this problem by utilizing a heater assembly that may be attached to a drain connection on the air cooler heater.
In one aspect, embodiments disclosed herein relate to a heater assembly for a fluid reservoir including an outer housing coupled to a flange on the fluid reservoir, an inner tubular member disposed within the outer housing, the inner tubular member having a central passageway therethrough, wherein an annulus is formed between the outer housing and the inner tubular member, and a heating device coupled to a lower end of the outer housing and having heating elements which extend upwardly into the central passageway of the inner tubular member.
In other aspects, embodiments disclosed herein relate to a heat exchanger including a fluid reservoir and a heater assembly coupled to the fluid reservoir, the heater assembly including an outer housing, an inner tubular member disposed within the outer housing, the inner tubular member having a central passageway therethrough, wherein an annulus is formed between the outer housing and the inner tubular member, and a heating device coupled to a lower end of the outer housing and having heating elements which extend upwardly into the central passageway of the inner tubular member.
In yet other aspects, embodiments disclosed herein relate to a method of heating water in a fluid reservoir including coupling a heater assembly to the fluid reservoir, the heater assembly including an outer housing, an inner tubular member disposed within the outer housing, the inner tubular member having a central passageway therethrough, wherein an annulus is formed between the outer housing and the inner tubular member, and a heating device coupled to a lower end of the outer housing and having heating elements which extend upwardly into the central passageway of the inner tubular member. The method further includes heating water present in the central passageway of the inner tubular member, wherein heated water exits from an upper end of the inner tubular member and circulating unheated water from the fluid reservoir downward through the annulus and into the central passageway of the inner tubular member.